As a promising green technology, microwave heating is highlighted by its high efficiency and low consumption, especially in the fast pyrolysis treatment for e-waste recycling. Electric discharge induced by microwave–metal interaction plays a significant role in the process, and its contribution to heat generation is, however, always hard to define qualitatively through direct experiments. In this simulation, a microwave heating model featuring the pulsed microwave–metal (MW-m) discharge was designed in multi-dimensions, using COMSOL Multiphysics software, to emphatically probe the depth and extent of the hot-spot effect as well as its auxo-action on the pyrolysis process of waste printed circuit boards (WPCBs). The energy loss generated by MW-m discharge was added into the models in the form of a built-in fluctuating heat source, and it is found that at a relatively low microwave energy-to-heat conversion rate (31.5%, 220.5 W), due to the unique thermal effect of microwave–metal discharge, it can achieve an ideal pyrolysis effect. Based on the results, the instantaneous heat by discharge is generated in the similar trend of radiation pulses, and the local temperature of discharge spots can reach more than 2000 K the instant the discharge occurs, shortening the overall pyrolysis from dozens of minutes to around 200 s.

微波加热作为一种很有前景的绿色技术，以其高效、低耗的特点，特别是在电子垃圾回收的快速热解处理方面尤为突出。微波-金属相互作用引起的放电在该过程中起着重要作用，然而，它对发热的贡献总是很难通过直接实验定性定义。在该仿真中，使用 COMSOL Multiphysics 软件在多维度上设计了具有脉冲微波 - 金属 (MW-m) 放电特征的微波加热模型，以重点探索热点效应的深度和范围及其辅助- 对废印刷电路板 (WPCB) 的热解过程采取行动。MW-m放电产生的能量损失以内置脉动热源的形式加入模型中，结果表明，在较低的微波能热转化率（31.5%，220.5 W）下，由于微波-金属放电的独特热效应，可以达到理想的热解效果。结果表明，放电瞬间产生的热量与辐射脉冲的趋势相似，放电点局部温度在放电瞬间可达200​​0 K以上，使整体热解从几十分钟缩短到200分钟左右。 s。